Device for utilizing the heat radiated from kilns



Jan. 8, 1929. 1,698,313

F. LUTHER DEVICE FOR UTILIZING THE HEAT RADIATED FROM KILNS Filed March4, 1927 m: In: EEC

V War/29y Patented Jan. 8, 1929.

'UNITED STATE-S PATENT OFFICE.

FRITZ LUTHER, OF DESSAU, GERMANY, ASSIGNOR TO THE FIR-M G. POL YSIUS, OF

DESSAU, GERMANY.

DEVICE FOR UTILIZING THE HEAT RADIATED FROM KILNS.

Application filed March 4, 1927. Serial No. 172,830.

This invention relates to a device for utilizing the heat radiated fromkilns, especially rotary kilns. The principal object of my inventionconsists in providing a kiln construction by means of which a part ofthe heat which is used for burning all kinds of material in the kiln maybe recuperated in order to improve still further the operation of thekiln from an economical point of view. The invent-ion consistsessentially therein that 'the cooling and combustion air is introducedinto a cooling jacket provided around the kiln, said cooling jackethaving preferably the shape of a hollow cylinder, and that said airafter having been heated in said jacket .is conveyed to the interior ofthe kiln through slots disposed around the periphery of the coolingzone. Thus the cooling air will be preheated at the inner walls of thecooling jacket and at the same time serve for cooling the walls of thekiln and the material therein. The technical progress which may thus beobtained by this device may still further be considerably increased byproviding around the aforementioned hollow cylinder which serves as acooling jacket proper heat receiving or collecting members, for instanceribs, radiators or the like, along which air is likewise pressed ordrawn in for the purpose of preheating. The heat thus recuperated maynow be utilized for any desired purpose and even be returned wholly orpartly to the kiln.

The cooling drum in order toform the aforementioned hollow cylinder maybe constructed in different ways. For the purpose in view it isessential that upon the inner wall of the cooling drum, there aredisposed nozzles through which the cooling air may be passed into theinterior of the kiln. The inner surface of the hollow cylinder orcooling drum in accordance to this,- for in stance, may be equipped witha plurality of cooling shovels or plates which are provided with smallslots in order to permit discharge of the preheated cooling andcombustion air.

The invention is illustrated diagrammatically and by way of example onthe accompanying drawing of which Fig. 1 is an axial section of a devicedesigned according to this invention, and Fig. 2 a cross-section in theplane A-B of Fig. 1, as seen from the left to the right.

The cooling drum 71 for instance may form a continuation of the rotarykiln (i, in axial direction thereof, only the righthand end of said kilnbeing shown in Fig. 1. In this manner the combustion as well as thepreliminary and the final cooling may take place in a continuous orunitary tube, composed of the kiln a and the cooling drum h. The latteralso may be driven separatively from the kiln and arranged, for.instance, below the latter. This arrangement would not form a departurefrom my mvention. The cooling drum h is constructed in the form of ahollow cylinder and on the inner surface of said hollow cylinder thereare arranged a plurality of shovel-shaped plates 6 which form slots 0.The cooling air which is blown-in at the end of the cooling drum h bymeans of special nozzles d enters into the interior of the kiln by wayof said slots 0. Thus an intense preheating of the cooling air andsimultaneously therewith a cooling of the plates 6 and of the materialto be burned in the kiln will be obtained. The nozzles d project from ahollow ringf which is supplied with air by means of a fan through a pipe9. In addition to the nozzle d which serve for blowing the cooling airinto the hollow cylindrical cooler 71., additional nozzles i may beprovided, said additional nozzles blowing cooling air into a protectivejacket in rovided around said cooling drum h. Furt ermore, heatabsorbing members, for instance, in the form of radiating ribs Z or thelike may be arranged on the interior wall of said jacket 7: and on theexterior wall of said cooling drum h, as indicated in Fig. 1. Thepreheated air may be used for a variety of purposes, such as drying rawmaterial, coal or the like, or it may be conducted wholly or partly backinto the kiln.

said cooling drum and said apertures therein into the interior of saidkiln.

2. A device for utilizing the heat radiated from kilns, comprising incombination, a-

cylindrical heat absorbing cooling drum associated witha kiln, saidcooling drum hav for passing air through the hollow space intermediatesaid walls and through apertures into the interior of the kiln, acooling acket enclosing said cooling drum, heat-absorbing members in theform of cooling ribs provided intermediate said drum and said jacket,and means for passing additional air into said jacket past saidheat-absorbing members.

4. A device for utilizing the heat radiated from kilns, comprising 1ncombination, a heat-absorbing drum having an interior and an exteriorwall, shovels provided on said interior wall and forming aperturestherein, means for passing air through the hollow. space intermediatesaid walls and through said apertures past said shovels intotheiinterior of the kiln, a jacket enclosing said drum, additionalheatrabsorbing members intermediate said drum and said jacket, and meansfor passing additional air into said jacket past said heat-absorbingmembers.

5. A device for utilizing the heat radiated from' kilns, comprising 1ncombination, a

heat-absorbing drum associated with a kiln, said drum having an interiorand an exterior wall, said interior wall comprising a plurality ofdistributed shovel-shaped members formingbetween them slots whichterminate into the interior of said drum, and means for passing air intothe hollow space intermediate said walls and through said slots intothe-interior of the kiln.

6. A device for utilizing the heat radiated from kilns, comprising incombination, a heat-absorbing drum associated with a kiln, said drumhaving an interior and an exterior wall, apertures in said interiorwall, nozzles arranged at the free end of said drum and bein directedtowards the hollow space interme iate said walls, and means forsupplying air to said nozzles to pass said air through said hollow spaceand said apertures into the interior of the kiln.

7. A device for utilizing the heat radiated from kilns, comprising incombination, a heat-absorbing drum having an interior and an exteriorwall, apertures in said interior wall, projections provided on saidexterior wall, a jacket enclosing said latter wall, projectionsinteriorly of said jacket, a set of nozzles arranged at the free end ofsaid drum and bein space intermediate said walls, a further set ofnozzles directed toward said jacket, and means for supporting air toboth setsof said nozzles.

In testimony whereof I afiix my signature.

FRITZ LUTHER.

directed towards the hollow

